Process of purifying sugar-juices.



rates PATE T tribe.

HENRI GOUTHIEBE, 0F PARIS, FRANCE, ASSIGNOR TO GUSTAVEDNARD JUNIUS, OF LONDON, ENGLAND.

FiUCESS @F PU REFYENG SUGAR- JUECES.

SEECIFIGATIOH forming part of Letters Patent No. 704,027, dated July 8, 1902.

Application filed May 7y 1901. Serial No. 59,079- (No specimens.)

To all whom it may concern:

Be it known that I, HENRI GOUTHIERE, a citizen of the Republic of France, and a resident of Paris, France, have invented certain new and useful Improvements in Processes of Purifying Sugar, of which the following is a specification.

This process is based upon the action of ferric fluorid (Fe Fl on sugar syrup in presence of small quantities of lime, (0:10.) The principal reactions which have to be considered will be stated in the following sections:

First. The ferric fluorid '(Fe Fl added to the syrup in the shape of a concentrated solution is decomposed under the influences of the dilution and of the heat, and thus hydrofluoric acid (HFl) and oXy-iiuorids of a more or less insoluble character and variable composition are formed. These two substances precipitate certain albuminoid matters contained in the syrup, and, further, the hydrofluoric acid (HFl) neutralizes by its antiseptic properties the action of certain fermenting substances which are always contained in the syru SeEond. When milk of lime is added to the syrup, prepared as above, a precipitate of insolublehydrated ferric oxid (Fe2O 3lI O) and fluorid of calcium (OaFl is produced. These two substances,wl1ich are formed in a nascent state in the syrup, complete the purification commenced and described in section]. by precipitating albuminoid and other foreign substances. The syrup decants easily, and the filtering is rapid. This is not the case with the simple defecation by lime, for, besides the slight purification which it effects, it produces a voluminous and gelatinous precipitate, and

the filtering of the syrup is thus rendered niorediiiicult; butwhcn ferric fluorid (Fe Fl is used the ferric oxid (FY2 0 and the clacium fluorid (Oalil,) effect not only a good purification, but give at the same time a totallydififerent precipitate,which can easily be separated by filtering.

Third. The clear syrup after having been purified by ferric fluorid, as described in sections 1 and 2, always contains some traces of iron, (be) which cannot be removed by alkalira. In order to eliminate this metal completely, it is precipitated as phosphate of iron (F PO by phosphoric acid (I-I PO,) or by the acid phosphates of alkaline earths.

Having described the general principles of my process, I may now state the manner in which the process is used with the raw juice of beet-root. A concentrated solution of ferric fluorid (Fe,Fl is added to the diffusionjuice which has a temperature of 40 centigrade maximum. This operation may be performed in the existing carbonation apparatus provided with mechanical stirrers. A precipitation of albuminoid substances and other foreign bodies takes place, and this precipitation is completed by adding a small quantityof milk of lime and by heating to to centigrade. The decomposition of the ferric fluorid (Fefil is thus completed, and insoluble calcium fluorid (GaFl and hydrate of ferric oxid (Fe O 3II O) are formed. These two compounds, produced in the nascent state, form, with the albuminoid and other substances, a precipitate which is easily removed, leaving the syrup perfectly clear. This syrup may be filtered by the ordinary filter-presses which are used for the carbonation processes. To the filtered clear syrup, which is of alkaline reaction, is then added an acid phosphate of alkaline earths .or ordinary phosphoric acid, (H PO Thus a precipitate of phosphate of iron, (P0,)2Fe and phosphate of calcium, (POQZOa is formed. This syrup is then heated to 80 to centigrade and filtered by filter-presses, and the filtering may be completed by mechanical filters. The clear filtered syrup is now evaporated and treated in the ordinary manner. By these operations a purification of a higher type is obtained than that resulting from the denble and treble carbonation process which is generally employed in beet sugar works. The quantity of lime which is required is insignificant, O.3 to 0.4 kilograms for one hundred kilograms of beet-root are sufficient as against 2.5 to 3.5 kilograms used in the processes which are employed at present. By not using the carbonation process a considerable part of the apparatus which is required for this operation is suppressed. The quantity of foam resulting from the purification by my process is much less considerable than that resulting from the carbonation process, and consequently the loss of sugar in the sediment is considerably diminished.

Since only a small quantity of lime is employed by me, the transformation of a part oi the albuininoid substance is avoided. This transformation takes place with the double and treble carbonation processes, where a great excess of lime is used at a rather high temperature, causing the generation of aminoniacal vapors,whichescape, and amides, which form soluole organic non-sugar, and thus interfere with crystallization.

Having thus described the nature of my process, I claim as my invention- 1. The process of purifying sugar-juice, which consists in treating it with ferric [luorid, substantially as described.

2. The process ofpurifying sugar-juice, which consists in treating it with ferric fluorid in the shape of a concentrated solution, substantially as described.

3. The process of purifying sugar juice which consists in treating it with ferric fluorid and adding milk of lime.

4. The process of purifying sugar-juice which consists in treating it with a concentrated solution of ferric finorid and adding milk of lime whereby calcium fiuorid and hydrated ferric oxid are produced in a nascent state aud act to purify and clarify the juice, substantially as described.

5. The process 'of purifying sugar -;iuice which consists in treating it with ferric fluorid, in adding milk of lime, and in then precipitating the iron as a phosphate, substain tially as described.

In testimony whereof I have signed my name to this specification in the presence or". two subscribing witnesses.

HENRI G OUTIIIERE.

Witnesses; 7

PAUL RICHARD Fmnmucn, EDWARD l. MACLEAN. 

